In a display unit of an electronic device such as a mobile telephone, there is used a liquid crystal panel for lowering the power consumption and for reducing the size and weight of the electronic device. For this liquid crystal panel, there has been demanded a higher image quality, as a high-information still or moving image is distributed according to the wide spreading of the mobile telephone in the recent years.
As the liquid crystal panel for realizing the high image quality of the display unit of the electronic device, there is known the active matrix type liquid crystal panel using a thin film transistor (as will be abbreviated into the “TFT”) liquid crystal.